He had next to nothing to do before Charlie Austin's goal, for which he wasn't exactly culpable.
Cameron Borthwick-Jackson 6
Solid but totally unspectacular. He did about as much as could've been hoped, but nothing more.
Daley Blind 5
Was one of the few United players who attempted to put Southampton's defence under pressure by trying ambitious passes. Unfortunately they were almost all rubbish.
Chris Smalling 5
Smalling didn't actually have much to do, though admittedly he could've been any one of a number of defenders to blame for Southampton's winner.
Matteo Darmian 5
Darmian was pleasingly solid before limping off with an injury, though he didn't offer anything in attack.
Morgan Schneiderlin 5
Schneiderlin didn't exactly show what his old team were missing, with a rather scrappy performance in which he could often be seen breaking up Southampton attacks with clumsy fouls. Still, I suppose that's a greater contribution than that offered by ...
Marouane Fellaini 2
Fellaini gets a two and not a one because he didn't literally manage to lose United the game, despite doing everything in his power to do so. He gave the ball away deep in United's half at least twice, and is showing no signs of actually being able to kick a football. His continued presence is as inexplicable as Van Gaal's.
Jesse Lingard 3
We've heard unconfirmed reports that Lingard was indeed on the field.
Ander Herrera 4
Van Gaal's bashed the fun out of almost all of his United teammates, so it makes sense that sooner or later Herrera would fall victim to the Dutchman's dour ways. The creativity and dynamism he often offers was sadly lacking, and United were much the worse for it.
Anthony Martial 5
As ever, he tried things, though in a team in which no one else is able to offer competent support, he was fighting a losing battle.
Wayne Rooney 4
Rooney's back! Rooney's back!
No, he isn't; he's gone for good.
Juan Mata 4
Offered nothing, though should probably still have started the game.
Paddy McNair 4
Definitely should've done better for the goal.
Adnan Januzaj 4
... and shouldn't have given the foul away leading up to the goal. But then again, he's not a defender, which Van Gaal seems yet to realise.